The easy cleaning of paint brushes and roller covers saturated with paint has always presented a problem. One solution is to use a manually powered machine to spin the saturated brush or roller cover, thus using centrifugal forces to spin paint from the brush or roller cover. Machines operated on this principle first appeared in the mid 1950's and are described in U.S. Pat. Nos. 2,794,265 and 2,884,709 to M. M. Kruger and U.S. Pat. No. 2,912,769 to L. Kruger. The disclosures of the foregoing three patents are incorporated herein by reference.
In brief, these machines comprise a hollow canister within which a rotatable tubular shaft rests. Attached to the bottom of the tubular shaft beyond the canister is a paint applicator holding device configured to hold either a paint brush or a roller cover. The top of the canister is capped by a cover which has an opening therethrough. A drive rod proceeds through the opening in the cover and into the tubular shaft. The drive rod has a uniformly-twisted spiralling blade portion and a handle portion. At the distal end of the spiral portion is an outwardly-extending flange. A clutch disk member is mounted on the spiral portion of the drive rod above the top of the tubular shaft and below the canister cover. The clutch disk is able to freely slide on the spiral portion along an opening in the clutch disk through which the spiral portion passes. The clutch disk has a plurality of radi-ally-extending arms. The top of the tubular shaft connects to a wheel having upwardly-extending triangularly-shaped lugs.
As the drive rod is pushed into the canister, the spiral portion rotates the clutch disk. As the clutch disk rotates, the arms contact vertical faces of the triangularly-shaped lugs. This forces the wheel, the tubular shaft and the paint applicator holding device to rotate.
The upstroke of the drive rod rotates the clutch disk in the direction opposite its rotation during the downstroke. However, the clutch disk arms now contact a slopped face of the triangularly-shaped lugs and slide up and over without forcing counter rotation of the wheel, tubular shaft or paint applicator holding device. Thus, the spinning direction of the holding device is always in the same direction.
The upward stroke of the drive shaft is limited by the flange mounted to the twisted portion contacting the clutch disk member.
However, the drive rod is known to pull from the canister after use enlarges the opening in the clutch disk until the drive rod flange can pass. This can create a dangerous situation. Accordingly, it would be beneficial to provide a safer drive shaft having a drive rod less likely to be pulled from the canister during the upward stroke.